MOSCOW, September 10. /TASS/. Squadrons of An-2 military transport planes will drop airborne troops and check air defense systems in the course of the surprise combat readiness inspection in Russia’s Central Military District, the press service of the Russian Defense Ministry said on Thursday.

"In all, more than ten An-2 crews of the Russian aerospace forces will be involved in the surprise check," the ministry said, adding that this type of planes was difficult to spot due to small echoing area in radar illumination.

The surprise combat readiness check in the Central Military District began on Monday at the order from the Supreme Commander-in-Chief of the Russian Armed Forces, President Vladimir Putin, and will last till September 12. The drills involve about 95,000 servicemen, more than 7,000 weapons and military hardware and about 170 warplanes.